Design of a high power density Halbach BLDC motor for an electric vehicle propulsion

Summary The electric drives used for vehicle propulsion need to be highly efficient and high power dense to improve the performance of electric vehicles (EV) and make them competent in transportation applications. In the similar lines, this paper proposes a radial flux brushless direct current (BLDC) motor with surface magnet rotor with a Halbach array. The magnetic equivalent circuit of the motor is derived; nonlinear electromagnetic analysis carried out and arrived at performance characteristics for an EV propulsion. The proposed topology is compared with conventional BLDC motor with surface mount magnets and found an increment of 20% in power density. The hardware is realized, tested for its performance and the results are closely matching with design parameters. This paper proposes Radial Flux BLDC motor with halbach array of magnets. The proposed motor is capable of delivering higher power with compact size resulting in high power density motor applicable for energy efficient EV propulsion. The magnetic equivalent circuit has been derived and equations developed which will be useful for optimisation of auxiliary and main magnet dimensions to arrive at an efficient BLDC motor design. The proposed topology compared with surface magnet and found an increment of 20% in power density. The hardware is realised, tested for its performance and the results are closely matching with design parameters